Understanding of formation, gastrointestinal breakdown, and application of whey protein emulsion gels: Insights from intermolecular interactions.

Whey protein emulsion gel is an ideal model food for revealing how the multilength scale food structures affect food digestion, as their structure and mechanical properties can be precisely manipulated by controlling the type and intensity of intermolecular interactions between protein molecules. However, there are still significant understanding gaps among intermolecular interactions, protein aggregation and gelation, emulsion gel formation, gel breakdown in the gastrointestinal tract (GIT), and the practical use of whey protein emulsion gels, which limits their GIT-targeted applications. In this regard, the relationship between the structure and digestion behavior of heat-set whey protein emulsion gels is reviewed and discussed mainly from the following aspects: (1) structural characteristics of whey protein molecules; (2) how different types of intermolecular interactions influence heat-induced aggregation and gelation of whey protein in the aqueous solutions and the oil-in-water emulsions, and the mechanical properties of the final gels; (3) functions of the mouth, the stomach, and the small intestine in processing of solid foods, and how different types of intermolecular interactions influence the breakdown properties of heat-set whey protein emulsion gels in GIT (i.e., their respective role in controlling gel digestion). Finally, the implications of knowledge derived from the formation and gastrointestinal breakdown of heat-set whey protein emulsion gels for developing controlled delivery vehicles, human satiety enhancers, and sensory modifiers are highlighted.

The Possible Involvement of Glucagon-like Peptide-2 in the Regulation of Food Intake through the Gut-Brain Axis.

Food intake regulation is a complex mechanism involving the interaction between central and peripheral structures. Among the latter, the gastrointestinal tract represents one of the main sources of both nervous and hormonal signals, which reach the central nervous system that integrates them and sends the resulting information downstream to effector organs involved in energy homeostasis. Gut hormones released by nutrient-sensing enteroendocrine cells can send signals to central structures involved in the regulation of food intake through more than one mechanism. One of these is through the modulation of gastric motor phenomena known to be a source of peripheral satiety signals. In the present review, our attention will be focused on the ability of the glucagon-like peptide 2 (GLP-2) hormone to modulate gastrointestinal motor activity and discuss how its effects could be related to peripheral satiety signals generated in the stomach and involved in the regulation of food intake through the gut-brain axis. A better understanding of the possible role of GLP-2 in regulating food intake through the gut-brain axis could represent a starting point for the development of new strategies to treat some pathological conditions, such as obesity.

In-ovo injection of Bacillus subtilis, raffinose, and their combinations enhances hatchability, gut health, nutrient transport- and intestinal function-related genes, and early development of broiler chicks.

An experiment was conducted to assess the response of chicks to in-ovo injection of Bacillus subtilis (probiotic), raffinose (prebiotic), and their combinations. The study used 1,500 embryonated eggs allotted to 10 groups/ 6 replicates (150 eggs/group). The experimental treatments were: 1) un-injected control (NC); 2) sham (sterile distilled water) (PC); 3) probiotic 4 × 105CFU/egg (LBS); 4) probiotic 4 × 106CFU/egg (HBS); 5) prebiotic 2 mg/egg (LR); (6 prebiotic 3 mg/egg (HR); 7) probiotic 4 × 105CFU + prebiotic 2 mg/egg (LBS+LR); 8) probiotic 4 × 105CFU + prebiotic 3 mg/egg (LBS+HR); 9) probiotic 4 × 106CFU + prebiotic 2 mg/egg (HBS+LR); and 10) probiotic 4 × 106CFU + prebiotic 3 mg/egg (HBS+HR). Results showed that in-ovo inclusion of Bacillus subtilis, prebiotic, and their combinations improved hatchability, yolk-free chick weight, and chick weight compared to the control group. Moreover, the in-ovo treatment reduced residual yolk weight on the day of hatch compared to the control group. Different levels of in-ovo B. subtilis alone or combined with raffinose significantly (P ≤ 0.001) reduced total bacterial count and total yeast and mold count compared to the negative control group. Total coliform and E. coli decreased significantly (P ≤ 0.001) in groups treated with probiotics, prebiotics, and synbiotics with different doses during incubation compared to those in the control. Clostridium spp. was not detected in the groups injected with B. subtilis alone or combined with raffinose. In-ovo probiotics and synbiotics (LBS+LR & LBS+HR) significantly (P ≤ 0.001) increased ileal villus length compared to other groups. In-ovo treatment increased mRNA expression of JAM-2 compared to the control group. The fold change significantly increased in group LBS+HR for genes MUC-2, OCLN, VEGF, SGLT-1, and EAAT-3 compared to the negative control. In conclusion, in-ovo injection of a low dose of B. subtilis plus a high or low dose of raffinose can positively affect hatching traits, cecal microbial populations, intestinal histomorphometry, nutrient transport- and intestinal function-related genes, and chick quality of newly hatched broiler chicks.

Microbiota-gut-brain axis: interplay between microbiota, barrier function and lymphatic system.

The human gastrointestinal tract, boasting the most diverse microbial community, harbors approximately 100 trillion microorganisms comprising viruses, bacteria, fungi, and archaea. The profound genetic and metabolic capabilities of the gut microbiome underlie its involvement in nearly every facet of human biology, from health maintenance and development to aging and disease. Recent recognition of microbiota - gut - brain axis, referring to the bidirectional communication network between gut microbes and their host, has led to a surge in interdisciplinary research. This review begins with an overview of the current understandings regarding the influence of gut microbes on intestinal and blood-brain barrier integrity. Subsequently, we discuss the mechanisms of the microbiota - gut - brain axis, examining the role of gut microbiota-related neural transmission, metabolites, gut hormones and immunity. We propose the concept of microbiota-mediated multi-barrier modulation in the potential treatment in gastrointestinal and neurological disorders. Furthermore, the role of lymphatic network in the development and maintenance of barrier function is discussed, providing insights into lesser-known conduits of communication between the microbial ecosystem within the gut and the brain. In the final section, we conclude by describing the ongoing frontiers in understanding of the microbiota - gut - brain axis's impact on human health and disease.

Experimental Protocols Used to Mimic Gastrointestinal Protein Digestion: A Systematic Review.

Bioactive peptides derived from native proteins modulate physiological processes in the metabolic pathways. Given that multiple protocols in the literature mimic the digestion of dietary components, gathering studies that use such models directed at protein digestion processes is critical. This systematic review aimed to gather evidence that adopted adequate experimental models to simulate human protein digestion. The databases searched were PubMed, Web of Science, ScienceDirect, Embase, Virtual Health Library, and Scopus. A total of 1985 articles were found, resulting in 20 eligible in vitro studies. The Office of Health Assessment and Translation was used to evaluate methodological quality. Seven studies used plant-based protein sources, twelve used animal protein sources, and one used both. The duration of the oral phase varied, although 60% of the studies employed a protein digestion period of 120 min. Amylase, pepsin, and pancreatin enzymes were utilized in 40% of the studies, with pH levels of 7, 3, and 7, respectively, during the oral, gastric, and intestinal phases. The INFOGEST harmonized static model was adopted by 65% of the studies; INFOGEST is the most effective model for simulating gastrointestinal protein processes in humans and can be used to answer several research questions because it describes experimental conditions close to the human physiological situation.

More Than a Gut Feeling─A Combination of Physiologically Driven Dissolution and Pharmacokinetic Modeling as a Tool for Understanding Human Gastric Motility.

In vivo studies of formulation performance with in vitro and/or in silico simulations are often limited by significant gaps in our knowledge of the interaction between administered dosage forms and the human gastrointestinal tract. This work presents a novel approach for the investigation of gastric motility influence on dosage form performance, by combining biopredictive dissolution tests in an innovative PhysioCell apparatus with mechanistic physiology-based pharmacokinetic modeling. The methodology was based on the pharmacokinetic data from a large (n = 118) cohort of healthy volunteers who ingested a capsule containing a highly soluble and rapidly absorbed drug under fasted conditions. The developed dissolution tests included biorelevant media, varied fluid flows, and mechanical stress events of physiological timing and intensity. The dissolution results were used as inputs for pharmacokinetic modeling that led to the deduction of five patterns of gastric motility and their prevalence in the studied population. As these patterns significantly influenced the observed pharmacokinetic profiles, the proposed methodology is potentially useful to other in vitro-in vivo predictions involving immediate-release oral dosage forms.

Optogenetic techniques for understanding the gut peristalsis during chicken embryonic development.

Gut peristaltic movements transport ingested materials along the gut axis, which is critical for food digestion and nutrient absorption. While a large amount of studies have been devoted to analyzing the physiological functions of peristalsis in adults, little is known about how the peristaltic system is established during embryogenesis. In recent years, the chicken developing gut has emerged as an excellent model, in which specific sites along the gut axis can be genetically labeled enabling live imaging and optogenetic analyses. This review provides an overview of recent progress in optogenetic studies of gut peristalsis. Analyses with an improved channelrhodopsin-2 variant demonstrated that the peristalsis can artificially be generated in the developing gut. These studies unveiled novel functional coordination between different regions along the gut axis. In addition, imaging with GCaMP6s, a genetically encoded calcium indicator, enabled a fine mapping of developmental changes in the peristaltic patterns as Ca2+ signals. These advanced techniques will broaden our knowledge of how embryonic peristalsis is established at the cellular and molecular level, leading to the understanding of physiological and pathological processes in adult peristalsis.

Intersexual patterns of the digestive tract and body size are opposed in a large bird.

The appropriate structure of the digestive tract is crucial for individual adaptation to ecological conditions. In birds, the length of the small intestine, responsible for food absorption, is generally believed to be positively correlated with body size. In this study, we investigated the variation in small intestine length in the White Stork (Ciconia ciconia), a monomorphic species without visible sexual dimorphism, but characterized by differing parental efforts, which can be reflected by the small intestine lengths between the sexes. We examined the relationship between small intestine length and body size within the sexes. Our findings show that male White Storks have significantly shorter small intestines than females, despite having larger body sizes than the latter. Furthermore, we found a significant relationship between body size and small intestine length, but it was of a different nature in the two sexes. Males exhibited a previously unreported phenomenon, whereby increasing body size was associated with shortening small intestines, whereas females exhibited the opposite pattern. These novel findings shed light on the anatomical adaptations of the digestive tract in birds.

[The gut, a whistleblower, in the early stages of Parkinson's disease]. / L'intestin, lanceur d'alerte, dans les prémices de la maladie de Parkinson.

The enteric nervous system (ENS), often called the "second brain", plays a crucial role in regulating digestive functions. Dysfunctions of the ENS are associated with several diseases such as Parkinson's disease. Recent studies suggest that early digestive disorders, notably chronic constipation, may be early signs of this neurodegenerative disease. Three-dimensional imaging of the ENS offers new insights into early diagnosis, in particular through the analysis of intestinal biopsies. This new research axis raises questions about the intestinal cause of Parkinson's disease, and opens the door to a better understanding and earlier treatment of this disease.

Title: L'intestin, lanceur d'alerte, dans les prémices de la maladie de Parkinson. Abstract: Le système nerveux entérique (SNE), souvent qualifié de « deuxième cerveau ¼, joue un rôle crucial dans la régulation des fonctions digestives. Des dysfonctionnements du SNE sont associés à diverses maladies telles que la maladie de Parkinson. Des études récentes suggèrent que les troubles digestifs précoces, notamment la constipation chronique, pourraient être des signes avant-coureurs de cette maladie neurodégénérative. L'imagerie tridimensionnelle du SNE offre de nouvelles perspectives pour un diagnostic précoce via notamment l'analyse de biopsies intestinales. Ce nouvel axe de recherche soulève des questions sur l'origine intestinale de la maladie de Parkinson et ouvre la porte à une meilleure compréhension et une prise en charge anticipée de cette maladie.

Dehydrated and live black soldier fly larvae as environmental enrichment in indigenous slow-growing chickens: performance, gut health, and chitinolytic enzyme activity.

The demand for sustainable and ethically farmed animal products is on the rise as consumers become more environmentally and animal welfare conscious. The need to diminish the consumption of soybean meal is urgent, and companies are looking for ways to respond to this necessity by looking for alternatives to soybean meal. This study assessed the impact of introducing whole dehydrated and live black soldier fly larvae (BSFL) into the diet of an indigenous chicken breed as environmental enrichment. A total of 144 39-day-old male Bianca di Saluzzo chickens were distributed among 18 pens and assigned to three different experimental groups. The control group received a diet where soybean meal was entirely replaced by alternative ingredients. The two experimental groups were given the same diet supplemented with 5% of the expected daily feed intake of whole dehydrated BSFL or whole live BSFL. Throughout the trial period (from the bird age of 39-174 days of age), live weight was recorded every 21 days, and the average daily gain, daily feed intake, and feed conversion ratio were calculated. The time required for the birds to consume the larvae was recorded three times a week. At age 147 and 174 days, 12 birds per treatment were selected based on mean live weight and slaughtered. Measurements included hot and chilled carcass weights, organ weights (spleen, liver, heart, stomach), breast and thigh muscle weights, and the corresponding yields were calculated. Acid protease activity was measured in proventriculus extract, and chitinase and chitosanase activity was calculated based on the release of reducing sugars from chitin or chitosan. The results showed little improvement in final live weights and daily feed intakes of the animals fed the insect larvae compared with control birds. Larva supplementation had no negative impact on the overall well-being of the animals assessed by blood analysis and histopathological assessment of the intestinal tract, spleen, and liver. No differences were found between the dehydrated vs live insect larvae consumption times, with all larvae being eaten up very rapidly (< 3 min). The birds fed BSFL showed an increase in chitinase activity. These findings support the potential use of whole BSFL as a form of environmental enrichment, particularly in their dehydrated form, being more convenient to use and store, which would also encourage the uptake of this practice by farmers.

MoPill a novel gastrointestinal positioning system (GPS): New technology to navigate the alimentary tract highway.

BACKGROUND: Evaluation of gut motility in clinical practice is currently limited. A novel medical system (MoPill™) consisting of a capsule that wirelessly transmits radiofrequency signals to assess motility via 3D location, was used to conduct this study. The objectives were to: (1) confirm the safety of the MoPill™ system; (2) compare the 3D location transmitted by the capsule to its location captured by abdominal x-rays; 3 determine gastric emptying (GE), whole gut transit time (WGTT) and segmental transit times. METHODS: The MoPill™ system consists of an electronic capsule (2 × 1.2 cm), eight color-coded adhesive sensors (6 × 5.5 cm), a recorder (15 × 11 × 2 cm), and software on a laptop. Four sensors were applied to the abdomen and four to the back. Healthy subjects who had fasted overnight ingested a 250-calorie protein bar, 17 oz. of water, followed by an activated capsule. No further caloric contents were permitted for the next 5 h. At 1, 5, and 24 h (if the capsule had not been expelled), upright abdominal X-rays (AP and lateral) were obtained to assess the location of the capsule, which was compared to the gastrointestinal positioning system (GPS) location determined by the MoPill™ system. Identification of the capsule's anatomical location by the MoPill™ system was based on (1) the 3D (x, y, z) location; (2) time; (3) trajectory (e.g., going up the right side of the body signified ascending colon); (4) frequency of contractions (e.g., 3 cycles/min for the stomach); and (5) milestone relationship (e.g., pyloric passage must follow the end of gastric contractions). GE was determined first by the end of the 3 cycles/min rhythmic movement of the stomach and then again by pyloric expulsion on 3D location. Small intestine transit was taken as the duration from pyloric expulsion to arrival in the cecum. Colon transit time was determined by calculating the duration from 3D arrival in the cecum to passage of the capsule out of the body (i.e., loss of signal accompanying a bowel movement). KEY RESULTS: Ten healthy subjects (five women; mean age 34; mean BMI 24) were enrolled, and nine provided reliable data. The variation between the x-ray and the estimated (i.e., identified by the MoPill™ system) location of the capsule was within an average of 3.5 cm (range 0.9-9.4 cm). The mean GE was 3.1 h. The small intestine's mean transit time was 4.3 h. The mean colonic transit time was 17.6 h. There were no adverse events recorded during the study. CONCLUSIONS & INFERENCES: MoPill™ is a novel gastrointestinal positional system that accurately identifies the location of a capsule compared to an X-ray. MoPill™ system also recognizes GE, small bowel, colonic, and WGTT as well as segmental gut location and movement characteristics. MoPill™ offers the potential for new insights into GI motility disorders not attainable by current modalities.

The developmental mechanics of divergent buckling patterns in the chick gut.

Tissue buckling is an increasingly appreciated mode of morphogenesis in the embryo, but it is often unclear how geometric and material parameters are molecularly determined in native developmental contexts to generate diverse functional patterns. Here, we study the link between differential mechanical properties and the morphogenesis of distinct anteroposterior compartments in the intestinal tract-the esophagus, small intestine, and large intestine. These regions originate from a simple, common tube but adopt unique forms. Using measured data from the developing chick gut coupled with a minimal theory and simulations of differential growth, we investigate divergent lumen morphologies along the entire early gut and demonstrate that spatiotemporal geometries, moduli, and growth rates control the segment-specific patterns of mucosal buckling. Primary buckling into wrinkles, folds, and creases along the gut, as well as secondary buckling phenomena, including period-doubling in the foregut and multiscale creasing-wrinkling in the hindgut, are captured and well explained by mechanical models. This study advances our existing knowledge of how identity leads to form in these regions, laying the foundation for future work uncovering the relationship between molecules and mechanics in gut morphological regionalization.

Midgut morphology of the predator mosquito Lutzia bigoti (Diptera: Culicidae) and its implications for feeding behavior.

Lutzia mosquitoes (Theobald, 1903) are predaceous during their larval stages, but the adult feeding is not clearly understood, especially in relation to blood feeding. In case these mosquitoes are harmless to humans and related animals, they can be useful in biological control of mosquito vectors of pathogens. Investigating the midgut morphology is a good strategy to understand the feeding behavior of this species. The midgut in Lutzia bigoti Bellardi, 1862 displays two distinct portions, a thin anterior midgut and a more dilated posterior midgut. Digestive cells form a single epithelium in the midgut. These cells have long and packed microvilli at their apex and membrane infoldings at their basal portion, the basal labyrinth. The epithelium is supported by a basal lamina. Regarding their cytoplasm, it is noteworthy the abundance of mitochondria, distributed in an apical-basal fashion, and also a whirl-shaped endoplasmic reticulum in the posterior midgut. Basal cells are also found in the midgut of L. bigoti, resembling regenerative cells. The general organization of L. bigoti's midgut closely resembles that of numerous hematophagous mosquitoes previously documented. However, it diverges due to the presence of a peritrophic matrix even when exclusively fed on sugary solutions. Peculiar aspects of L. bigoti's midgut are discussed and compared to those of other mosquito species.

The enteroendocrine axis and its effect on gastrointestinal function, nutrition, and inflammation.

PURPOSE OF REVIEW: Gastrointestinal (GI) dysfunction limits enteral nutrition (EN) delivery in critical illness and contributes to systemic inflammation. The enteroendocrine (EE) axis plays an integral role in this interface between nutrition, inflammation, and GI function in critical illness. In this review, we present an overview of the EE system with a focus on its role in GI inflammation and function. RECENT FINDINGS: Enteroendocrine cells have been primarily described in their role in macronutrient digestion and absorption. Recent research has expanded on the diverse functions of EE cells including their ability to sense microbial peptides and metabolites and regulate immune function and inflammation. Therefore, EE cells may be both affected by and contribute to many pathophysiologic states and interventions of critical illness such as dysbiosis , inflammation, and alternative EN strategies. In this review, we present an overview of EE cells including their growing role in nonnutrient functions and integrate this understanding into relevant aspects of critical illness with a focus on EN. SUMMARY: The EE system is key in maintaining GI homeostasis in critical illness, and how it is impacted and contributes to outcomes in the setting of dysbiosis , inflammation and different feeding strategies in critical illness should be considered.

The origin of intraluminal pressure waves in gastrointestinal tract.

The gastrointestinal (GI) peristalsis is an involuntary wave-like contraction of the GI wall that helps to propagate food along the tract. Many GI diseases, e.g., gastroparesis, are known to cause motility disorders in which the physiological contractile patterns of the wall get disrupted. Therefore, to understand the pathophysiology of these diseases, it is necessary to understand the mechanism of GI motility. We present a coupled electromechanical model to describe the mechanism of GI motility and the transduction pathway of cellular electrical activities into mechanical deformation and the generation of intraluminal pressure (IP) waves in the GI tract. The proposed model consolidates a smooth muscle cell (SMC) model, an actin-myosin interaction model, a hyperelastic constitutive model, and a Windkessel model to construct a coupled model that can describe the origin of peristaltic contractions in the intestine. The key input to the model is external electrical stimuli, which are converted into mechanical contractile waves in the wall. The model recreated experimental observations efficiently and was able to establish a relationship between change in luminal volume and pressure with the compliance of the GI wall and the peripheral resistance to bolus flow. The proposed model will help us understand the GI tract's function in physiological and pathophysiological conditions.

Particle size of insoluble fibres and gelation of soluble fibres influence digesta passage rate throughout the gastrointestinal tract of finishing pigs.

Fibres, as abundant in agricultural by-products, exhibit a large range of physicochemical properties that can influence digestive processes such as digesta mean retention time (MRT), thereby affecting nutrient digestion kinetics. In this study, we investigated the effects of particle size of insoluble fibres, and gelation of soluble fibres on MRT of liquids, fine solids, and fibrous particles in the different segments of the gastrointestinal tract (GIT) of pigs. Twenty-four boars (51.6 ± 4.90 kg) were allocated to four diets; two diets contained 15% wheat straw, either coarsely chopped or finely ground (1-mm screen), two diets contained 27% wheat bran without or with the addition of 10% low-methylated pectin. After 14 days of adaptation to the diet, a total collection of faeces was performed to determine the total tract digestibility of nutrients. Thereafter, pigs were fed diets supplemented with tracers for at least 5 days and dissected following a frequent feeding procedure to approach steady-state passage of digesta. The MRT of liquids (Co-EDTA), fine solids (TiO2), and fibrous particles (Chromium-mordanted fibres) in the different segments of the GIT were quantified. In the stomach, particle size reduction of straw decreased the MRT of fine solids by 02:39 h, and fibrous particles by 07:21 h (P < 0.10). Pectin addition to the wheat bran diet reduced the MRT of fine solids by 03:09 h, and fibrous particles by 07:10 h (P < 0.10), but not of liquids, resulting in less separation between digesta phases in the stomach compared with the bran diet (P < 0.05). In the mid-small intestine (SI), pectin addition reduced the MRT of fibrous particles and the separation between fibrous particles and fine solids. No further effects of particle size reduction of straw nor pectin addition on MRT and digestibility of starch, nitrogen, or fat were observed in the SI. In the large intestine (LI), particle size reduction of straw reduced separation between fibrous particles and fine solids (P < 0.10), while pectin addition had no effects. Total tract, non-starch polysaccharide degradation of straw was poor (∼31%), and unaffected by particle size reduction (P > 0.10). The complete fermentation of pectin did not influence the degradation of wheat bran fibres (∼51%). In conclusion, the effects of particle size of insoluble fibres and gelling properties of soluble fibres on the passage of digesta phases were most pronounced in the stomach, but less prominent in distal segments of the GIT.

Comparing finite viscoelastic constitutive relations and variational principles in modeling gastrointestinal soft tissue deformation.

The mechanical attributes of soft tissues within the gastrointestinal (GI) tract are crucial for the effective operation of the GI system, and alterations in these properties may play a role in motility-related disorders. Various constitutive modeling approaches have been suggested to comprehend the response of soft tissues to diverse loading conditions. Among these, hyperelastic constitutive models based on finite elasticity have gained popularity. However, these models fall short in capturing rate- and time-dependent tissue properties. In contrast, finite viscoelastic models offer a solution to overcome these limitations. Nevertheless, the development of a suitable finite viscoelastic model, coupled with a variational formulation for efficient finite element (FE) implementation, remains an ongoing challenge. This study aims to address this gap by developing diverse finite viscoelastic constitutive relations and applying them to characterize soft tissue. Furthermore, the research explores the creation of compressible, nearly incompressible, and incompressible versions of viscoelastic constitutive relations, along with their variational formulation, to facilitate efficient FE implementation. The proposed model demonstrates remarkable accuracy in replicating experimental results, achieving an R2 value exceeding 0.99.

Neuroimmunophysiology of the gastrointestinal tract.

Gut physiology is the epicenter of a web of internal communication systems (i.e., neural, immune, hormonal) mediated by cell-cell contacts, soluble factors, and external influences, such as the microbiome, diet, and the physical environment. Together these provide the signals that shape enteric homeostasis and, when they go awry, lead to disease. Faced with the seemingly paradoxical tasks of nutrient uptake (digestion) and retarding pathogen invasion (host defense), the gut integrates interactions between a variety of cells and signaling molecules to keep the host nourished and protected from pathogens. When the system fails, the outcome can be acute or chronic disease, often labeled as "idiopathic" in nature (e.g., irritable bowel syndrome, inflammatory bowel disease). Here we underscore the importance of a holistic approach to gut physiology, placing an emphasis on intercellular connectedness, using enteric neuroimmunophysiology as the paradigm. The goal of this opinion piece is to acknowledge the pace of change brought to our field via single-cell and -omic methodologies and other techniques such as cell lineage tracing, transgenic animal models, methods for culturing patient tissue, and advanced imaging. We identify gaps in the field and hope to inspire and challenge colleagues to take up the mantle and advance awareness of the subtleties, intricacies, and nuances of intestinal physiology in health and disease by defining communication pathways between gut resident cells, those recruited from the circulation, and "external" influences such as the central nervous system and the gut microbiota.